Newbie considering an e-conversion. But what.

[Raboa]

Hi, I use both a BBS02 and a rear hub motor. They are used to commute, shopping and with a trailer.
In my opinion the BBS02 is improved with a gear sensor, this adds more cost to the purchase. The BBS02 cannot be used with standard chainrings unless you use an adapter which again more cost. The BBS02 is a great system but in my opinion it is not perfect out of the box.
Hub motors can be used with standard chainrings and I feel they don't require any additional equipment to tweek the system. If I was to buy for the first time again I would buy a rear hub motor with a frame battery.

As you can see people prefer different types and are passionate about this. People will read this post and agree / disagree with my all/some of my comments.

Both systems require the purchase of tools, BBS02 will require a locking spanner, a hub motor will require a file (I used a 10.2mm round file).

If possible try both types, most of all, enjoy using whatever system you buy.

 

[cannon]

Re the chainring, I should have added to my post above that due to the increase offset of the Bafang chainring I use a bling ring to correct this on the mtb so first gear alignment is acceptable. However, on the 9 speed hybrid I kept the Bafang 44t chainring and bought a cheap ultrawide cassette (11-46) and and do not use first gear. So in effect I have a 8 speed 11-40 cassette and the resulting larger steps between gears works well with the 250w motor.

 

[Sturmey]

.....what hub drives need is someone does an OSF project like the one for the Tongsheng TSDZ2. ...........

You may be interested, the German Forum has a long thread on an OSF project on the Lishiu controller. (Its readable in English on my win 7 with Google Chrome using normal translate). I dont know how useful it is or how well its devoloped.

Open Source Firmware für Lishui Controller

nachdem die offene Firmware für den Kunteng ja mehr oder weniger fertig entwickelt ist, habe ich mir einen Lishui als nächstes Opfer ausgesucht. Vorteil der Lishui-Controller: 1. viele haben den Programmieranschluß schon herausgeführt, man muß also nichts auf der Platine rumlöten 2. viel...

www.pedelecforum.de

 

[Woosh]

Good find, Sturmey, and thank you for that.
PS: the project repository does not seem to have a Lishui branch.
OpenSource EBike · GitHub

 

[guerney]

Can a KT controller limit the throttle to a UK legal 3.7mph?

 

[Yak]

What a great thread, lots of knowledge on show here. I don’t have much of that, but I’m getting some experience…
I fitted a 36v rear hub motor with a 12.5ah battery and a speed sensing (Lishui) controller to my road bike. I didn’t bother with a throttle. Set at level 2, assistance comes on when my speed drops to 17-18kmh and increases without any input from me as I get slower and slower, until it is giving me full power at perhaps 11kmh. Range is down to how fast I can keep going ie how hilly. My longest ride is 204kms, but the battery was at 100% at the end! the highest I’ve climbed on 1 charge is 1450m with less than 20% charge left. My friend bought the same kit but is 58kgs and has climbed 1850m with 40% left. It really is down to rider input/weight. I’m still 120kgs, and we have now covered a little under 12,000kms. I renewed the chain after 5800kms and it was knackered (so cassette too), but it’s replacement has only now reached it’s replacement wear limit. I hope some of that is useful.

 

[Sturmey]

PS: the project repository does not seem to have a Lishui branch.
OpenSource EBike · GitHub

I think the above link is used only by endless sphere. There is a wiki page. I think is still has a lot of work to do.
https://www.pedelecforum.de/wiki/doku.php?id=elektrotechnik:open_source_firmware_fuer_lishui_-controller

 

[Nealh]

Can a KT controller limit the throttle to a UK legal 3.7mph?

Yes if you want to one sets the C4 parameter to value 1 or use value 2 and input the speed limit manually, other wise you set it to 25km/h and opt for pedal 1st option using parameter P4 value 1. As long as the throttle isn't twist and go on it's own , you can set it to 25km/h and be legal.

 

[guerney]

Yes if you want to one sets the C4 parameter to value 1 or use value 2 and input the speed limit manually, other wise you set it to 25km/h and opt for pedal 1st option using parameter P4 value 1. As long as the throttle isn't twist and go on it's own , you can set it to 25km/h and be legal.

Do hub drive motors (or contollers) burn out more often than crank drive motors or controllers? If not, my next ebike might have to be a hub drive with a KT controller, because an automatic UK legal throttled assisted start would be kinder to my very old damaged knees than my existing bafang 250W 01B. I've got used to gearing down before stops at lights, but hill starts and starts after unanticipated sudden stops are painful, and sometimes impossible without mounting the pavement (or turning and going downhill) to change gear, because I haven't installed a throttle at all. Maybe I shouldn't worry about legality so much, reading these forums one could conclude that pretty much every ebike rider uses a throttle.

 

[vidtek]

Do hub drive motors (or contollers) burn out more often than crank drive motors or controllers? If not, my next ebike might have to be a hub drive with a KT controller, because an automatic UK legal throttled assisted start would be kinder to my very old damaged knees than my existing bafang 250W 01B. I've got used to gearing down before stops at lights, but hill starts and starts after unanticipated sudden stops are painful, and sometimes impossible without mounting the pavement (or turning and going downhill) to change gear, because I haven't installed a throttle at all. Maybe I shouldn't worry about legality so much, reading these forums one could conclude that pretty much every ebike rider uses a throttle.

If you retro-fit an older bike then a throttle is still legal; that is my understanding. That was the reason I chose an old Specialized Crossroads (circa 1980's) aluminium bike that weighs about 19kg. No fancy-smanchy disk brakes for me, no suspension other than a pneumatic seat post. It's done me proud and am now up to about 1500miles with the Whoosh Tongsheng mid-drive kit 48v.

The reasons you outline are the exact same reasons I require a throttle, the other alternative you may consider is a nexus gear system hub gears like the old Sturmey Archers, I still can't get used to derailleur gears, especially in a quick stop situation.

 

[guerney]

If you retro-fit an older bike then a throttle is still legal; that is my understanding.

Are you certain about this? I thought that the ebike as a whole had to be "Old" - both bike and edrive manufactured and sold together as an integrated whole, for the use of throttle limited to 15.5mph to be UK road legal. Do you happen to have a link to the regulations which deals with this specifically?

 

[Nealh]

I have not had a KT controller fail completely in 7 years of use, the only fault i have had is thermal cutting out due to over heating. KT are pretty damn reliable.
All I will say is, if your riding is hilly and slow or off road and you use high current then opt for a 9 fet controller over the 6 fet one.

 

[vidtek]

Are you certain about this? I thought that the ebike as a whole had to be "Old" - both bike and edrive manufactured and sold together as an integrated whole, for the use of throttle limited to 15.5mph to be UK road legal. Do you happen to have a link to the regulations which deals with this specifically?

No I did this two years ago and my memory isn't that great--I can't remember what I had for dinner last night--let alone what I did 2 years ago.......but I'm pretty sure it is as I stated, you can ask Tony or Andy at Whoosh-they're always lurking about on this forum so they may pick this up and advise you conclusively.

 

[guerney]

I have not had a KT controller fail completely in 7 years of use, the only fault i have had is thermal cutting out due to over heating. KT are pretty damn reliable.
All I will say is, if your riding is hilly and slow or off road and you use high current then opt for a 9 fet controller over the 6 fet one.

The parts most likely to fail are the fets then? There's no gearing to ease strain on the electrics with a rear hub I guess.

 

[guerney]

No I did this two years ago and my memory isn't that great--I can't remember what I had for dinner last night--let alone what I did 2 years ago.......but I'm pretty sure it is as I stated, you can ask Tony or Andy at Whoosh-they're always lurking about on this forum so they may pick this up and advise you conclusively.

I'll leave my throttle disconnected for now:

Pedelec Law - The Details

Thank you for a very full and interesting post. I know that the UK legal motor size limit is 250W but am puzzled how Bosch manage to make a whole range of motors at prices that go up with torque from 40Nm up to 85Nm, are these all 250W, just that the more expensive ones have more powerful...

www.pedelecs.co.uk

 

[Woosh]

Are you certain about this? I thought that the ebike as a whole had to be "Old" - both bike and edrive manufactured and sold together as an integrated whole, for the use of throttle limited to 15.5mph to be UK road legal. Do you happen to have a link to the regulations which deals with this specifically?

the new rule since 1/1/2016 applies exclusively to manufacturers and importers.
Twist and go throttles are not allowed.
You can see why I program ready made e-bikes with throttle function only enabled after you pedal a bit. That is to make the throttle inactive on start up so not a twist and go.
This new rule does not apply to retrofit and kits.
Some companies supply ready made bikes without the throttle to comply with the rules then sell throttles separately as a plug-in retrofit (ie fit after use on roads).

Kits are on the other hand, not regulated.

 

[RichD1]

So do the regulations limit the power for 'old' converted bikes with new kits?

 

[vidtek]

So do the regulations limit the power for 'old' converted bikes with new kits?

Yes, 250w is the max permitted. 15mph legal max.

 

[vfr400]

I'll leave my throttle disconnected for now:

Pedelec Law - The Details

Thank you for a very full and interesting post. I know that the UK legal motor size limit is 250W but am puzzled how Bosch manage to make a whole range of motors at prices that go up with torque from 40Nm up to 85Nm, are these all 250W, just that the more expensive ones have more powerful...

www.pedelecs.co.uk

When you use a KT controller, you can have a legal throttle. Throttles are legal, but there are some restrictions on how they control the bike. The two rules are:
1. It can work independently to 6km/h to launch you from start.
2. It can be used to control the speed and power at all speeds up to 25km/h as long as the power to the motor stops when the pedals stop rotating.

There is no rule about how fast the pedals must rotate, nor how hard you have to pedal. The KT controller has settings to apply both the two rules above simultaneously. In other words, you can launch with the throttle and air-pedal once you're moving while you control the power/speed with the throttle.

A throttle set up like above can give you a massive advantage in your ebike control system and is well worth fitting.

 

[vfr400]

Yes, 250w is the max permitted. 15mph legal max.

That's not true at all. There is no limit on output power for ebikes in the UK. It's a myth based on a misunderstanding of the rules. The standard specifies that the motor must be "rated" at no more than 250w. How much power you put through it is up to you, and there is no rule as to how the motor is rated other than that it mustn't burn at 250w. There are very few ebikes on the road in the UK that don't produce more power than 250w. 400w to 500w is typical of most legal ebikes. Some (legal) are much higher.